1. Why no support for parentheses? (Try adding them - I think that
it might make things clearer.)

> However in the final table this grammar seems to be ambiguous. I> actually first transformed the above into this disambiguous form.

> S -> E> E -> E-T | T> T -> T/F | F> F -> F++ | G> G -> ++E | id

2. What is it about G that gives rise to a different kind of rule
from those for T and F?

3. Suppose that you reversed the priority of prefix- and postfix-++
(which I think you might have backwards anyway, but I'm not in a
C frame of mind right now) -- what would be different about your
transformed grammar?